Finally tonight, you're going to be hearing a lot in coming days about our person of the week sheryl sand berg, the coo of facebook. She's announcing a kind of movement to power more women to the top. Here's a stark fact. Tonight women earn almost 60% of all college degrees. But they hold only 14% of the top jobs in america's big companies. So sandburg has written a book called lean in. When I talked to her last may, she said we have to teach our daughters to believe they are going to run the company, if we want the workplace to change for all women and their families. Sheryl sandburg says she wants to see young women celebrate ambition and never tell themselves they have to give up money or their passion because they want a family. She even heard her own daughter say she couldn't be president and why? Because I want to be a mommy. My daughter wrote a song with all the presidents in it. Her first question was, mommy, why are they all boys? And I thought, good question. What happened is that men believe they can do both. Have careers and families. Women think there's going to be pressure and have too choose. They start thinking I'm not going to be able to do all this because I want to have I child one day. Do not lean back. Lean in. Put your foot on the gas pedal and keep it there until the day you have to make a decision and then make a decision. And that decision, she says, could be changing the workplace. She hopes the younger generation remember what these opportunities would have meant to their grandmothers. My grandmother was an incredible woman. In her generation, you didn't work outside the home. But she had breast cancer and survived young. So she started selling watches to raise money for breast cancer research out of her car. And she did this and built into what was a business that anyone would be proud to have. I often think about what would have happened to my grandmother, what her career would have been like had she been born when i was born. She's written the work and she's teaching women confidence while sitting a table of power. She remembers eight years ago after her first child, she'd sneak out of the office early to be home. I didn't lie about it, but i wasn't out there giving speeches either. I did a lot of things women do, kept my lights in my office on. No more. She said publicly she's going to leave. I started saying to people, i go home at 5:30 to have dinner with my kids and everyone knows that. I started saying that not only for me, but to make it safe for everyone else who works there. Can all women go in and say, this is what they need for their lives? Not every job is this flexible. Even though technology is making more jobs more flicksible. She acknowledges she's lucky she has real choices. But she argues that only when women stay and succeed in the workplace can they help make the workplace better for the women who do not. No one gets to the corner office by sitting on the side, not at the table. We've got to get women to sit at the table. she told a graduating class at barnard, this is the cross roads, believe you're the one who will recreate the world. I hope that you -- yes, you -- each and every one of you have the ambition to run the world. Because this world needs you to run it. Around the world are counting on you. I'm counting on you. and so we choose sheryl sandburg. And by the way, she says they have encouraging signs all over the facebook office and her favorite is, what would you do if you were not afraid?

This transcript has been automatically generated and may not be 100% accurate.

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